In brake systems for motor vehicles, pumps are employed to enable active braking. The pumps are designed in such a way that they are able to pump sufficient brake fluid into the brake lines for any requested braking action in a predefined time period. One minimum demand comes from driver assistance or vehicle dynamics control systems, which initiate full braking or brief, individual braking of individual wheels to stabilize the vehicle in borderline situations. In this case a large volume of brake fluid must be pumped in a short time, so that a high rotational speed of the pumps is necessary.
However, high pump speed results in unacceptable noise generation.
During calibration, a rotational speed for the brake system is defined which represents a compromise between braking dynamics and noise generation. The compromise is determined on the basis of prior driving trials and empirical values from comparable brake systems. This results in considerable effort to find the compromise, as well as the risk of underestimating the requisite rotational speeds.